1. Field of the Invention
The present invention relates to a motorcycle with a drive shaft.
2. Description of Background Art
Generally a motorcycle has been known in which a rear fork is swingably provided on a body frame with a power unit, a rear wheel is provided at the rear end of the rear fork, and a drive shaft is provided between a gear case provided on a lateral side of the rear wheel and the power unit's output shaft to transmit output power of the power unit to the rear wheel through the drive shaft and gear case (for example, see JP-A No. 2006-96274).
In this type of motorcycle, the rear fork has a pair of left and right arms and each arm is a tube with a closed cross section.
However, in the above conventional structure, when the drive shaft is located inside one arm, the one arm must have a larger cross section than the other arm; in this case, it is necessary to increase the strength of the rear fork and reduce its weight while optimizing the rigidity balance.